Sodium borohydride hydrazinates: synthesis, crystal structures, and thermal decomposition behavior

Abstract

. (2015). Sodium borohydride hydrazinates: synthesis, crystal structures, and thermal decomposition behavior. Journal of Materials Chemistry A, 3 (21), 11269-11276. Sodium borohydride hydrazinates: synthesis, crystal structures, and thermal decomposition behavior AbstractMetallic borohydride hydrazinates are novel boron-and nitrogen-based materials that appear to be promising candidates for chemical hydrogen storage. Herein, sodium borohydride hydrazinates, including NaBH 4 ·N2H 4 and NaBH 4 ·2N 2 H 4 , were synthesized via a facile solution synthesis approach based on the solid-liquid reaction between NaBH 4 and hydrazine in tetrahydrofuran (THF) solution. The crystal structure of NaBH 4 ·2N 2 H 4 was solved to a monoclinic structure with unit cell parameters a = 8.4592(2) Å, b = 11.7131(2) Å, c = 6.4584(1) Å, and β = 100.0777(14)°, with space group A1a1 (9). Each Na + ion interacts with four neighboring N 2 H 4 molecules, leading to the formation of Na 4 [N 2 H 4 ] 4 4+ cationic chains along the a direction. Such cationic chains are surrounded by BH 4 − anions. The NaBH 4 ·xN 2 H 4 (x = 1, 2) was characterized by Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and mass spectroscopy (MS) to obtain a full picture of the relationship of the structure to the decomposition, which will be useful for future work on borohydride hydrazinates or the study of other B-N materials. Furthermore, magnesium borohydride hydrazinates were synthesized by ball milling the sodium borohydride hydrazinates with magnesium borohydride, and their thermal decomposition was investigated as well. differential scanning calorimetry (DSC), and mass spectroscopy (MS) to obtain a full picture of the relationship of the structure to the decomposition, which will be useful for future work on borohydride hydrazinates or the study of other B-N materials.Furthermore, magnesium borohydride hydrazinates were synthesized by ball milling the sodium borohydride hydrazinates with magnesium borohydride, and their thermal decomposition was investigated as well.

Tunable NaBH4 Nanostructures Revealing Structure‐Dependent Hydrogen Release

“…This could be due to the formation of excessive borohydride–amine complexes upon the reaction of NH 2 with BH 4 − at a higher concentration of amine. [ 25 ]…”

“…This could be due to the formation of excessive borohydride-amine complexes upon the reaction of ─NH 2 with BH 4 À at a higher concentration of amine. [25] For the TDA-stabilized NaBH 4 , the undefined morphologies of NaBH 4 -TDA-2.5 evolved into bar-like morphologies of increasing length for TDA concentration above 5 mM (Figure 2d and Figure S6, Supporting Information). Only spherical NaBH 4 nanoparticles were previously observed at a TDA concentration as low as 100 μM, [11b] and this indicates that TDA has two critical micelle concentrations (CMCs), which direct the growth of NaBH 4 into the sphere and/or bar-like nanostructures.…”

Synergetic effect of metal-organic framework UiO-66 and silver plasmonic nanoparticles on PET waste support in degradation of nerve agent simulant

“…3C, S1A). Moreover, typical peaks of AgNPs, prepared by chemical reduction, at ≈1500 cm -1 and 1650 cm -1 also appear [34]. X-ray photoelectron spectroscopy (XPS) demonstrates the appearance of 3.1 % of Zr after in situ growth of UiO-66 (Tab.…”

Mechanisms of partial hydrogen sorption reversibility in a 3NaBH4/ScF3 composite

“…5,6 In the past few decades, great attention has been paid to both hydrogen production technologies and a variety of hydrogen storage methods, [7][8][9][10] including the use of different compounds, 11,12 especially complex hydrides, of which borohydrides are typical representative. [13][14][15] These solid-state hydrogen storage materials offer some advantages over high pressure gaseous storage and low temperature liquid storage, such as high capacity, high safety, and low cost. In particular, alkali metal borohydrides are regarded as possible hydrogen carries, ascribed to their contribute to their high gravimetric and volumetric hydrogen density, together with good stability.…”

“…For the sake of improving the thermodynamic and kinetic properties of the thermal decomposition of NaBH 4 , many strategies have been taken, such as adding catalyst, building thermodynamic destabilization system, nano-engineering and chemical modications. 13,[23][24][25] For instance, NaBH 4 /MgH 2 system could full its decomposition before melting due to the formation of MgB 2 in the system. 26 Czujiko et al suggested that pure Mg could lower down the desorption temperature of NaBH 4 through catalytic effect.…”